We have all seen the price increases for Mini parts, especially CV joints. The single largest reason for the failure of this rugged assembly is contamination; dirt and moisture will destroy one very quickly! The CV rubber boot protects the joint at all angles but if your boot shows any sign of cracking or scuffing preventative replacement can save a lot of money. These boots are for the inboard CVs of later, or updated, rod change cars.
See also part number LMGREASE.